SIM808 GSM GPRS GPS BT MODULE + Arduino UNO

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1

Hi guys,

I am trying to get my SIM808 module working with Arduino UNO, but I can't and I don't know why, I really appreciate your help.

This is the board that I have:

CONNECTIONS:

SIM808 module and Arduino UNO are separately powered by my laptop (USB).

SIM808 UNO
RX PIN8
TX PIN7
GND GND

SIM is inserted on the the board and the problem is:
After I press the start button for 2 sec, the LEDs start blinking, when the LEDs are blinking I execute AT commands and I receive response, but after some seconds the LEDs stops blinking and when I execute AT commands I don't receive any response. I don't know why the LEDs stops blinking.

I upload a video with what is going on:

This is the code:

#include <SoftwareSerial.h>
SoftwareSerial mySerial(7, 8); //RX, TX

void setup()
{
   mySerial.begin(9600);   
   Serial.begin(9600);   
   delay(100);
}

void loop()
{
 
   if (Serial.available()>0){
     mySerial.write(Serial.read());
   }
   if (mySerial.available()>0){
     Serial.write(mySerial.read());
   }
}

I really appreciate your help.

Thank you guys.

2

UP

3

What kind of the power supply do you have to power your SIM808 ?

I looks like your modem has not enough power to work. And it needs quite a lot of power :slight_smile: